Furnace burner arrangement



Feb. 3, 1948. R. c. HOPKINS FURNACE BURNER ARRANGEMENT Filed Dec. 20, 1943 2 Sheets-Sheet l WMM@ Feb. 3, 1948. R. c. HOPKINS FURNACE BURNER ARRANGEMENT 2 Sheets-Sheet 2 Filed Dec. 20, 1943 Haber 6 Hoym Patented Feb. 3, 1948 UNITED sTATEs PATENT oFFlcE FURNACE BURNER ARBANGEMENT Robert C. Hopkins, Alliance, Ohio Application December 20, 1943, Serial No. 514.933 2 Claims. (01.1283-33) The invention relates to the arrangement of furnace burners and more particularly to an arrangement of burners for oil or gas fired melting furnaces of the type which is rotated upon its axis to charging and pouring positions.

Furnaces of this type are of horizontal, cylindrical shape, arranged to be rotated or oscillated upon their longitudinal axis, and are commonly provided with opposed, axially disposed burners at opposite ends. With such a construction and burner arrangement there is no practical Way of utilizing the waste heat of the furnace through a recuperator for preheating the air of combustion.

This is due to the fact that it is necessary to provide some permanent connection between the furnace and the recuperator. In the process of melting, the furnace is oscillated backward and held in this position for a sufiicient period of time to heat the refractory lining of the furnace so that when the furnace is turned back to charging and melting position the hot refractories are at the bottom of the metal. Because of this oscillation, it becomes diicult, if not impossible, to take waste heat from the charging and pouring door in a practical and economic manner.

On the other hand, if a burner is provided only at one end of the furnace so that waste heat may be taken from a central opening at the opposite end, then there is a zone of the refractories of the furnace nearest to the burner which is not impinged by the flame of the burner, since the flame is cone shaped and does not flare outward to a point where it contacts the furnace lining until it has reached a point substantially midway of the furnace.

Therefore. while a permanent connection may be made between the furnace and the recuperator, this type of burner arrangement is not satisfactory because it does not uniformly heat both end portions of the furnace.

It is therefore an object of the present invention to provide a furnace burner arrangement which overcomes the above mentioned difficilities and objections to the common forms of burner arrangements now in general use for a. melting furnace of this type, and to provide for adequate and uniform heating of the entire interior of the furnace while at the same time permitting a permanent connection between the furnace and the recuperator.

A further object is to provide a, burner arrangement which insures a complete distribution of the llame and gases throughout the entire furnace from one end to the other, and a permanent connection between said other end of the furnace and the recuperator.

Another object of the invention is to provide a burner arrangement for furnaces of this type referred to in which one burner is located axially at one end of the furnace, the other end of the furnace being provided with an axial opening connecting with the recuperator, another burner being tangentially located at the end of the furnace near the axial burner and arranged .for producing a tangential inflow of the fire stream into the furnace.

The above objects together with others which will be apparent from the drawings and following description or which may be later referred to, may be attained by constructing the furnace burner arrangement as shown in the accompanying drawings, in which Fig. l is a side elevation of a melting furnace with the burner arrangement, showing the connection between the same and a recuperator for receiving the waste heat from the furnace;

Fig. 2 an end view of the furnace shown in Fig. 1, and

Fig. 3v a transverse sectional view through the furnace taken as on the line 3 3, Fig. 1.

Referring now particularly to the drawings, in which similar numerals refer to similar parts throughout, the furnace is indicated generally at lli and the recuperator at il. As shown in the drawings the furnace is in the form of a horizontal cylinder comprising the metal shell i2 having a refractory lining I3 therein, this being a common type of melting furnace.

Trunnions I4 are formed at opposite ends of the cylindrical furnace shell and rests upon the casters I5, mounted upon the supporting frame I6. thus supporting -the furnace for rotating or oscillating upon its axis.

For the purpose of rotating the cylindrical furnace upon its axis a worm gear I1 is fixed to one `end of the furnace shell and meshes with the worin screw i8. Journaled in a bracket I9 supported upon the frame I5. A hand wheel 20, or equivalent device, may be mounted upon the worm shaft 2i `for the purpose of operating the worm screw torotate or oscillate the furnace upon its axis.

One end of the cylindrical furnace has an axf iaily located, conical opening 22 formed therein and an axially disposed burner 23 communicates therewith for discharging a lire stream axially into the furnace.

A tangentlally disposed. conical opening 24 is 3 formed through the tangential boss 2B at the end of the furnace adjacent to the burner 23 and a tangentially disposed burner 28 communicates with the opening 24, thus discharging a tangential nre stream into the furnace.

A charging or pouring opening 21, of conventional design, is provided in one side of the furnace as in usual and well known practice and so located that when the furnace is in the charsing or melting position, as shown in the draw-l ings, this opening is located at'the top.

Any suitable closure, as indicated generally at 28, may be provided for the charging and pouring opening in order to keep the same tightly closed execpt during the charging and pouring operation. i

An axially disposed opening 29 is formed in the end of the furnace opposite to the burner 23, for the purpose oi forming a permanent connection between the furnace and the recuperator l I, as shown in Fig. 1. In order to form this connection a short length of pipe 30 extends from the recuperator into the axial opening 29 of the furnace thus permitting the furnace to be oscillated or rotated upon its axis without interfering with the connection to the recuperator.

The waste heat from the furnace is thus conveyed directly into, the recuperator and as the gases of combustion pass through the recuperator, an exchange of air is eifected, which is discharged through the pipe 3i to the burners 23 and 26 to atomize and support combustion, thus providing an easy and simple method of preheating the air for atomization and combustion by directly connecting the recuperator with the furnace and not in any way interfering with either the operation, upkeep or repair of the furnace.

It will be obvious that with this arrangement of burners both an axial and tangential ame or iniiow is produced, the tangential burner supplying fiame to that portion of the furnace adjacent tothe axial burner which is not reached and heated by the axial re stream, thus completely filling the furnace with llame, which is necessary for the best results of both quality of metal and quantity of products. p

With this combination oi an axial ow from one burner and a tangential inflow from the other burner, there is a twisting or spiral motion of the dame and hot gases which by centrifugal force causes a moderate pressure of the'hot gases and flame over the entire area of the furnace, therefore being a distinct advantage and insuring a very complete distribution of the flame and gases throughout the entire furnace from one end thereof to thel other, not only balancing the furnace pressure but causing the fuel tobe combusted at kone burner by the action of the other.

The tangential inilow also has the eect of recuperating the fuel stream from the axial burner and this eilect is to greatly increase the rapidity of changing the fuel. such as oil, into gas. With the tangential burner at the same end of the furnace as the axial burners, the eect is 4 to cause a rapid heat exchange which results in higher efficiency and less tendency to what is known as gassing the metal."

The tangential inilow of the flame is especially well adapted for preheating the furnace preliminary to charging the metal. With the products of combustion discharging either through the charging and pouring opening, or directly into the recuperator, a spiralilow of name is actually induced from the burners at one end of the furnace to the outlet at the other end of the furnace, thereby preheating the furnace equally over Y the entire ilame swept surface. The tangential burner may be turned on for the preliminary heating of the metal charge, thereby preventing dame impingement over the charged metal, and any time after 'the metal goes to melt, both burners may be turned on to flnish the heat.

I claim:

1. In combination with a horizontal cylindrical furnace having a charging and pouring door in one side, an axially disposed opening in each end and a tangentially disposed opening adjacent to one end. a tangentially disposed burner communieating with the tangential opening and an axial burner communicating with the adjacent axial opening, the other axial opening forming a discharge port for the products of combustion of the burners. f

2. In combination with a horizontal, cylindrical furnace having a charging and pouring door in one side, an axially disposed opening in each end and a tangentially disposed opening adjacent to one end, a tangentially disposed burner located entirely outside of the furnace and arranged to register with said tangential opening whereby .the furnace may be rotated upon its axis to position said door at the top for charging and at the bottom for pouring, and an axial burner registering with the adjacent axial opening, the other axial opening forming a discharge port for the products of combustion of the burners.

ROBERT C. HOPKINS. v

REFERENCES CITED The following references are of record in the ille oi this patent:

UNITED STATES PATENTS 

